Tinderbox build fix.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@41513 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/bitmap.h

@@ -21,6 +21,7 @@
 #include "wx/string.h"
 #include "wx/gdiobj.h"
 #include "wx/gdicmn.h"  // for wxBitmapType
+#include "wx/colour.h"
 
 class WXDLLEXPORT wxBitmap;
 class WXDLLEXPORT wxBitmapHandler;